Fecundity of Wild Speckled Trout (Salvelinus fontinalis) in Quebec Lakes

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Abstract
For the present macroscopic study over 1,000 female speckled trout from the Laurentide Park in Quebec have been examined. Of this number, 747 specimens received special attention. In ovaries of adult trout 3 types of eggs were found: recruitment stock (Class a), maturing eggs (Class b) and atretic eggs (Class c). In the process of maturation, the number of eggs of Class b progressively decreases due to atresia, but their diameter becomes greater. Comparisons of fecundity between different trout populations should be made only when eggs are nearly mature. The diameter of ripe eggs just previous to spawning, preserved in formalin, varied from 3.8 to 4.8 mm. There is a direct relation between the number of ripe eggs and the size of the fish: the extreme numbers of eggs were 90 and 4,800 eggs, and the extremes of fork lengths of females were 6 and 22 inches. The fecundity is greater among fish from lakes richer in food. A simplified method of determining the number of eggs in ovaries was devised. The maturity of females was determined by a 7-digit system. The colour of flesh was classified by a 6-digit system.